New Madrid Earthquake Return? Don't Bet on It!

"ST. LOUIS — Just days after the 200th anniversary of a series of massive earthquakes in southeast Missouri, residents woke up Tuesday to a rumbling reminder that they live in one of the continent's most active seismic areas.
"The U.S. Geological Survey said the epicenter of a magnitude-4.0 earthquake at 3:58 a.m. was located near the town of East Prairie, Mo., roughly midway between St. Louis and Memphis. Several people in five states — Missouri, Illinois, Arkansas, Kentucky and Tennessee — felt the quake, along with scattered people in four others, as far away as North Carolina and Georgia, according to responses to the U.S. Geological Survey website.
"Only minor damage was reported, such as items falling from shelves, broken windows, minor cracks in walls and sidewalks, said Amy Vaughan, a geophysicist for the Geological Survey office in Golden, Colo. No injuries were reported." — Associated Press, 2/21/2012

List this Missouri resident in the "Not Concerned" column, please. After attending "It's Your Fault: A Conference Commemorating the 200th Anniversary of the New Madrid Earthquakes" on February 18 at the University of Missouri, I'm confident today's "rumbling reminder" was simply an aftershock from one of the most unusual earthquakes ever recorded.
Allow me to elaborate.
First to the dais at the conference was Walter Schroeder, MU associate professor emeritus of geography, who gave some historical background on the series of massive (8 or more?) earthquake which generated out of the New Madrid area between December 1811 and February 1212.
At the time, the area was a swamp, populated by maybe 1,500 folk. The state's last wild bison were found there in 1847, and bear and elk were there as late at 1867, so there was not a lot of manmade stuff to be damaged.
The folk who did live there had already experienced the arrival of Haley's Comet in September, and the Aurora Borealis was seen a few days before the first quake, so they were primed for "a time of extraordinaries" and "a terrible visitation of Providence."
Per recorded history cited, bottoms of lakes elevated and were later planted with corn. The muddy Mississippi changed to a reddish hue and produced a great deal of foam. Sparks sprung from the earth and whole forests were found fallen flat.
Men who make it their life's business to study earthquakes — Mian Liu, MU professor of geology, and Eric Sandvol, MU assistant professor of geology — made it pretty clear to me that the earth is made up of tectonic plates, along the edges of which most earthquakes occur. New Madrid is in the middle of one of these plates, which makes it unusual.
Unusual, but not exclusive. As Professor Liu pointed out, China has also had earthquakes at locations in the middle of tectonic plates, and they have recorded history of earthquakes that go back 3,000 years. The Chinese actually appoint individuals to record the effects of earthquakes.
For example, the Shaanxi earthquake of 1556 is the deadliest on record, killing 830,000 people and destroying a 520-mile-wide area. The Tangshan quake of 1976 killed a quarter of a million people. And on a lesser scale as far as strength and human loss – but far closer to home and our own time – there was the November 9, 1968 quake that originated in Illinois and was felt in 23 states.
Earthquakes are a fact of life, but another earthquake happening on the New Madrid fault, where the MU professors theorize the trembling like that today may be unique aftershocks 200 years after a most unique earthquake? Well, I put my money with Professor Liu:
"If you bet an earthquake will happen in the same place, the odds of winning are zero."